Effect of individual amino acids and glucose on activation and germination of Rhizopus oligosporus sporangiospores in tempe starter

Abstract

Aim: To understand the conditions promoting activation and germination of spores, and to contribute to the control of tempe starters. Methods and Results: Using microscopic counts of fluorescent labelled spores, the following results were obtained: (1) L-alanine plays an important role (of the same order as that of peptone) in stimulation of germination of dormant spores. Alanine can satisfy the requirements of carbon as well as nitrogen for spore germination; (2) L-proline, on the other hand, inhibits alanine uptake presumably by blocking/congesting transporters of spore cells, resulting in apparent low viability on agar media; (3) L-leucine and L-isoleucine slightly favour spore germination while L-arginine and L-lysine do not have any stimulating effect; (4) The stimulatory role of glucose was only evident in the presence of phosphate (in minimal medium); when glucose is used in the absence of phosphate, either alone or in combination with single amino acids its role is hardly distinguishable; (5) Phosphate plays a facilitating role in spore germination. Conclusions: Glucose and amino acids play important roles in activation and germination of sporangiospores of Rhizopus oligosporus in tempe starter (stored for 12 months). The ability and rate of germination of dormant/old sporangiospores of R. oligosporus, depend on their ability for uptake of individual amino acids and/or glucose. Significance and Impact of Study: New light was shed on the counteractive role of proline and the stimulating effect of phosphate. Soybeans subjected to traditional preparation for tempe making are heavily leached; germination of starter spores on such beans is sub-optimal, and bean processing could be optimized.

The Role of Aquaporins in pH-Dependent Germination of Rhizopus delemar Spores

“…Thus, the spore must be capable of sensing and responding to environmental signals. Spores of different fungal species have diverse requirements for the triggering of germination [ 5 , 8 , 9 , 14 , 15 , 57 – 59 ]. Nevertheless, spore dehydration during maturation seems to be a fundamental process that is common to all spore-producing fungi.…”

β-Amino-n-butyric Acid Regulates Seedling Growth and Disease Resistance of Kimchi Cabbage

“…Fungal spore germination have been stimulated or inhibited by endogenous and/or exogenous stimuli from the ambient environment (Macko et al, 1977; Tsurushima et al, 1995). Amino acid alanine promoted spore germination of Rhizopus oligosporus but proline negatively affected the spore germination (Thanh et al, 2005). Amino acids such as serine, alanine, glutamic acid, arginine and methionine inhibited conidial germination of A. alternata, whereas aspartic acid, phenylalanine and threonine stimulated the germination (Migahed and Nofel, 2001).…”

Viability and physiological state transitions of Rhizopus oligosporus sporangiospores in tempe starter culture

“…We found that certain amino acids, e.g. alanine, are functional as resuscitating agents (Thanh et al 2005). It will be of interest to the industry to optimize cheap media for the resuscitation of stored spore starters.…”